A vehicle collision discriminating device is known in which a hard impact absorbent material and a soft impact absorbent material are inserted inside a front bumper, and a collision detection tube filled with an incompressible fluid is inserted between the hard impact absorbent material and the soft impact absorbent material (see, for example, Japanese Patent Application Laid-open (JP-A) No. 11-310095 (FIGS. 13-15)). Further, a collision detection means is known in which plural through holes that penetrate in a vehicle front-rear direction are provided in a chamber member in order to adjust a deformation amount of the chamber member in accordance with a position in a longitudinal direction thereof, the through holes being filled with a foam resin (see, for example, JP-A No. 2007-290689 (FIG. 17 and paragraph [0103]).